Free synthesis software for linux

Balsa project is an asynchronous circuit synthesis system. Balsa is built around the Handshake Circuits methology, and it can generate gate level netlists from high-level descriptions in the Balsa language.

Both dual-rail (QDI) and single-rail (bundled data) circuits can be generated.

FMS stands for Fully Modular Synthesizer and is a tool to create all kinds of sounds from scratch.
You can play and sound (sine, triangular, etc.) with any property settings (frequency or volume) and modulations thereof.
It also features tools to save sounds, play .MUS music, graphically display sounds, and make real noise.
Main features:
Playing sounds
- with any frequency and volume
- one after another or at the same time (mixer) or both
- stereo (different sounds on different channels)
- like speech synthesis
- both on-the-fly playing with direct user access and asynchronous, pre-computed output
- with all modulation options described below
Making noise
- now although it tends to get noisy in any way, we mean real noise here
- in 4 different ways
- nearly-white noise
- narrow band noise
Modulating
- amplitude (volume)
- frequency
- minima, maxima, amplitude and frequency of the modulation (here the "Fully Modular" comes to existence)
- narrowness of the noise frequency band - experimental
Making music
- some-kind-of-midi-mapping mode (sound + envelope => instrument, FMS midi file format)
- auto-converter and player for MUS file format (Musplay)
- auto-composer for those who like a rather modern kind of music - experimental
- chords - experimental
Displaying
- spectrum of a sound
- oscillogram of a sound
Saving
- sounds as oscillograms in FMS file format (mathematical description, not complete wavetables)
- sounds as Fourier overtone amplitudes
- music in FMS midi format
- FMS output in wave format
- wave file sounds in FMS file format (auto-converter) - experimental
GUI
- a somewhat ugly and extremely limited tcl/tk gui
- FROCOR, an installation that connects the FMS sound backend to graphical interfaces and outputs
- a fully modular Qt GUI - experimental
Enhancements:
- synchronous mode (no more waiting!)
- bugfixes (no more screaming!)
- unscrewed display tools (no more segfaulting!)
- improved exacticity (no more discalculating!)
- UDS controlled sound backend (no more stupid jokes!)

FluidSynth is a real-time software synthesizer based on the SoundFont 2 specifications. FluidSynth project can read MIDI events from a MIDI input device and render them to an audio device using SoundFont instruments.
SoundFont files are composed of digital audio "samples" and additional instrument parameters. These files can be created or downloaded off the Internet. FluidSynth also has support for controlling effects in real time and can play MIDI files.
Note: FluidSynth was previously called IIWU Synth.
Enhancements:
- LASH support has been added.
- This release has improved command line argument handling, AMD-64 bugfixes, a few synthesis bugfixes, and other miscellaneous improvements.

Signs is a tool for logic synthesis and gate level simulation. Signss project main features include synthesis of RTL-style VHDL circuit descriptions and a dynamic graphical netlist viewer.
Supported formats include VHDL, ISCAS, and limited support for BLIF, Verilog, and EDIF netlists. Various true value and fault simulators and a combinational ATPG are included for circuit testing.
Aside from GUI mode, Signs has a pure command line mode and is fully scriptable in JavaScript and Ruby.
Main features:
- Written in Java, therefore platform-independent
- Aims to be VHDL93 compliant, at the moment a VHDL Subset is supported
- (Limited) support for non-synthesizable VHDL code, useful for testbenches
- Synthesis of RTL-style sequential VHDL process descriptions according to IEEE Std 1076.6
- Dynamic graphical netlist viewer supporting annotations (signal/gate names, signal values provided by simulators, faults)
- VHDL netlist output to file
- Input and output of netlists in ISCAS benchmark format
- Gate level true value simulators: event-based (any circuit), bit-parallel (combinational circuits only)
- Fault simulators: PPSFP, simple single faultsim
- Input and output of pattern lists in WGL format
- ATPG for combinational circuits: Implication-Graph based, PODEM
- Limited support for Verilog and EDIF netlists
- Fully scriptable in Rhino: JavaScript for Java and JRuby
- Pure command-line mode available besides GUI mode
- Integrated environment including source code and netlist structure tree views, build system, compilers and editors with syntax highlighting
Enhancements:
- While the release focus is clearly on bugfixes, there are also some feature improvements, such as enhanced test bench support and improved netlist and simulator views.
- The VHDL compiler has support for subprograms now and elaboration of big designs is much faster because of improved context handling.
- Internally, the intermediate representation layer was cleaned up, so intermediate objects form a proper tree now.

AlsaModularSynth project is a realtime modular synthesizer and effect processor.
Main features:
- MIDI controlled modular software synthesis
- Realtime effect processing with capture from e.g. "Line In" or "Mic In".
- Full control of all synthesis and effect parameters via MIDI.
- Integrated LADSPA Browser with search capability
- JACK Support
Modular synthesis is one of the most flexible and fascinating ways of making electronic music. The principles of voltage-controlled modular synthesis have been stated in the famous paper Voltage-Controlled Electronic Music Modules by Robert A. Moog , presented in 1964 at the Annual Convention of the Audio Engineering Society.
AlsaModularSynth is a digital implementation of a classical analog modular synthesizer system. It uses virtual control voltages to control the parameters of the modules. The control voltages which control the frequency e.g. of the VCO (Voltage Controlled Oscillator) and VCF (Voltage Controlled Filter) modules follow the convention of 1V / Octave. Read the first two pages of the Moog paper to understand why this logarithmic scale is so important.
A real analog synthesizer has a lot of knobs and switches which give immediate access to all important parameters of the generated sound. AlsaModularSynth can be controlled by MIDI controller boxes, like e.g. the Doepfer Pocket Dial . MIDI events can be assigned to module parameters in a very flexible way by using the Control Center dialog of AlsaModularSynth.

BruteFIR is a software convolution engine, a program for applying long FIR filters to multi-channel digital audio, either offline or in realtime. BruteFIRs basic operation is specified through a configuration file, and filters, attenuation and delay can be changed in runtime through a simple command line interface.
The FIR filter algorithm used is an optimised frequency domain algorithm, partly implemented in hand-coded assembler, thus throughput is extremely high. In realtime, a standard computer can typically run more than 10 channels with more than 60000 filter taps each.
Through its highly modular design, things like adaptive filtering, signal generators and sample I/O are easily added, extended and modified, without the need to alter the program itself.
Main features:
- Designed for realtime filtering of HiFi quality digital audio
- Up to 256 inputs and 256 outputs
- Input/output provided by external modules for maximum flexibility
- Default I/O modules provide support for sound cards and files
- Access multiple I/O modules (= several sound cards / files) at the same time
- 8 - 24 bit audio at any rate supported by sound cards
- Easy-to-use C language API to create your own I/O modules, for example to support more file formats, other sound card APIs, or generate test signals
- Mix/copy channels before and/or after filtering
- Cascade filters or build complex filter networks
- Simple C language API to create logic modules, to add new functionality
- Create your own logic module, for example to do adaptive filtering
- Provided is a logic module which implements a CLI accessible through telnet to manage runtime settings, and a dynamic equalier.
- Toggle/change filter in runtime
- Alter attenuation for each individual input and output in runtime
- Alter delay for each individual input and output in runtime
- Filter length limited only by processor power and memory
- Typical filter lengths are in the range 2048 - 262144 taps
- Reasonable low I/O-delay (typically 200 ms)
- Fixed I/O-delay, thus possible to sample-align with other processors
- Cross-fade for seamless filter coefficient changes.
- Redithering of outputs (HP TPDF)
- Overflow protection and monitoring
- 32 or 64 bit floating point internal resolution.
- Supports multiple processors
A few examples of applications where BruteFIR could be a central component:
- Digital crossover filters
- Room equalisation
- Cross-talk cancellation
- Wavefield synthesis
- Auralisation
- Ambiophonics
- Ambisonics
Among these, room equalisation and auralisation needs the longest FIR filters in the common case. Many applications can do with quite short filters actually, but the thing is that you will probably not need to compromise on the filter lengths when you use BruteFIR, even when sample rates go up.
However, BruteFIR is pretty useless by itself, since it is only a FIR filter engine. It does not provide any filter coefficients, thus it is not a filter design program. Also, due to its relatively high I/O-delay, BruteFIR is most suited for applications when the input signal is not live.

Dyne:bolic GNU/Linux is a live bootable cd, containing a whole operating system that works straight from boot, without the need to install or change anything on the hard disk.
If you like and want to have it on harddisk you can simply copy the /dyne directory on your computer: the simpliest installation ever!
Dyne:bolic is user-friendly: recognizes your hardware devices (sound, video, firewire, and USB), and offers a VAST range of free software applications for multimedia production, audio and video manipulation, sound composition and synthesis, 3D modeling, photography, peer2peer filesharing, web browsing, desktop publishing, word processing, cd burning, email, encryption, remote conferencing, funky games, a world atlas navigator and even more.
Advanced features include: a complete environment with the most advanced multimedia applications available on GNU/Linux, automatic clustering joining the CPU power between any other dyne:bolic on the local network, capability to work well on old PC (Pentium1 64Mb) and even XBOX game consoles, support to save and encrypt personal data and settings on a usb key. Dyne:bolic is shaped on the needs of media activists and artists to promote free speech as a tool for the production and not only the fruition of digital and analog
informations.
There is no company nor organization behind dyne:bolic, it is a grassroot effort to spread free software and the spirit of sharing information and knowledge.
Enhancements:
- OpenMosix automatical startup and discovery
- Mozilla suite 1.7.5 (Firefox and Thunderbird dropped)
- Mail encrypted with Sylpheed 1.0.3, GpgME and Enigma
- Virtual keybord for alternative access devices
- Nest now remembers xBox PAL/NTSC switch
- Wider PC laptop hardware support
Updated software:
- Blender-2.36, Ardour-0.9-beta28, Gimp-2.0.6, Xine-1.0
- Fix to Rezound linkage to libFOX 1.2
- Various fixes and documentation updates
- Shiny new splash screen in gtk2
- In case you have a DOCK (/dyne directory copied in your harddisk) you should upgrade it by using the one in this release. Booting the CD just answer YES when youll be prompted to UPGRADE..